Prevent date tree getting chopped (5)
I believe the answer is:
deter
'prevent' is the definition.
(thesaurus)
'date tree getting chopped' is the wordplay.
'date' becomes 'd' (common abbreviation eg in DOB, date of birth).
'getting' is a charade indicator (letters next to each other).
'chopped' indicates anagramming the letters.
'd'+'tree'='dtree'
'dtree' anagrammed gives 'DETER'.
(Other definitions for deter that I've seen before include "Dishearten" , "Inhibit" , "Discourage or prevent from doing something" , "Daunt" , "Hinder, discourage" .)